Generally, this invention relates to a method for preventing unwanted flow in any form from exiting a nozzle after an intended termination of flow. Specifically, the preferred embodiment of the invention focuses on a method for preventing the unwanted release or discharge of fuel drips from a fuel pump or delivery nozzle after an intended fuel delivery shut-off, through the use of a biased, one-way valve that is reconfigurable in response to a fuel delivery termination pressure and that itself may comprise at least one fluid obstruction element that rotates about (and is perhaps attached at) an axis that is aligned with a chord of a simple closed curve defined by the inner surface of the fuel conduit.
The desire to prevent unintended flow from a conduit such as a fuel pump nozzle after a main flow has been intentionally terminated in some manner (e.g., by closure of a main valve element) has been known for some time. Preventing such flow, typically in the form of drips or drops, but certainly also observed as a stream of fluid at times, prevents unwanted spillage, reduces waste, results in a more volumetrically accurate filling procedure, reduces the total emanation of vapors from the fluid into the ambient environment, and generally, results in a more economical filling operation, among other things. The reduction in total emanation of vapors from the fluid into the ambient environment may result in significant benefits to the environment, and in health benefits to persons in that environment, particularly upon consideration of the high numbers of fuel pump nozzles and the vast amounts of gasoline that are pumped through them on any given day in certain areas. Such benefits of post flow delivery shut-off accrue to both the seller of the fluid, the operator of the fluid delivery device, and the purchaser of the fluid, and are particularly apparent when the delivered fluid is a fuel such as gasoline or diesel, e.g., and the conduit.
At least one other prior art apparatus such as that disclosed in U.S. Pat. No. 5,620,032 to Dame is directed to preventing drips specifically from fuel nozzles. However, Dame""s disclosed device is not usable to block substantially all of the flow area of the fuel conduit because it discloses only a valve portion that is xe2x80x9cnearly rectangular in shapexe2x80x9d, and thus unable to completely obstruct the disc-shaped flow area of the disclosed fuel conduit. Also contributing to this aspect of the operation of Dame""s device is attachment of the disclosed valve portions along curved (instead of straight) sections, those curved sections being potions of the C-shaped ring(s). Such attachment prevents a more thorough blocking of the flow area and increases the possibility of unwanted passage of fuel around certain portions of the C-shaped ring to which no valve portion is attached, after a shut-off of the main flow. Such attachment might also inhibit facile rotation, as more resistance expectedly inheres in a rotation about a curved axis as compared with rotation about a straight axis.
There may indeed be known certain valve apparatus which is used in at least one embodiment of the instant invention""s methods to effectively prevent unwanted xe2x80x9cpost intended flow shut-offxe2x80x9d drips (a term including drops or any type of flow from the end of the relevant conduit). However, although such apparatus may be known (see, e.g. U.S. Pat. No. 4,005,732 and U.S. Pat. No. 3,965,926), their use to prevent flow from a fluid delivery conduit after an intended shut-off is riot. As these valves and the aforementioned xe2x80x9cpost intended flow shut-offxe2x80x9d drip problem have been known for some time now; the fact that these valves have not yet been used to prevent xe2x80x9cpost intended flow shut-offxe2x80x9d drips (including drops or any other unwanted flow such as stream flow) points to the non-obviousness of the present invention.
The present invention includes a variety of aspects which may be selected in different combinations based upon the particular application or needs to be addressed. In one basic form, the invention discloses the use of a known one-way valve in a novel manner to effectively prevent xe2x80x9cpost intended flow shut-offxe2x80x9d drips, including drops or other flow from a fluid delivery conduit. A more focused embodiment of the invention is the use of a known one-way valve in a novel manner or application to prevent xe2x80x9cpost intended fuel flow shut-offxe2x80x9d drips, drops or flow from a fuel delivery conduit. A preferred embodiment involves the use of a biased, one way valve that is reconfigurably responsive to a fluid flow shut-off pressure to prevent flow (e.g., drips, drops and/or a fluid stream) after an intended shut-off of fluid flow (this shut-off of fluid flow occurring via closing of a main valve element). The valve may comprise at least one fuel obstruction element that is rotatable about and/or attached at a chord of a simple closed curve (a circle or oval, as but two examples) defined by the inner surface of the fuel conduit, and in a preferred embodiment, the one way valve comprises two fuel obstruction elements rotatable about and attached at a respective chord of the simple closed curve. The two chords may be within a plane that is orthogonal to an axis of the fuel conduit, substantially collinear, and may bisect the simple closed curve. The valve may be retrofit within a conduit of an existing fuel nozzle, or a conduit extension (which includes the valve already, or within which the valve may be added) may be added to an existing conduit, so that an existing fuel nozzle may be drip-free during fuel delivery. Also, a factory adaptation is possible in which a non-extended conduit of the nozzle is adapted to incorporate the valve within it, or in which a conduit extension (which includes the valve already, or within which the valve may be added) is attached at the end of the non-extended conduit. Naturally, as a result of these several different and potentially independent aspects of the invention, the objects of the invention are quite varied.
One of the broad objects of at least one embodiment of the invention is to enable adaptation of existing fluid delivery conduits so that they may be operated with a decreased fluid flow out of a conduit end or opening occurring after an intended shut-off of a main valve element or other intended substantial termination of flow, as compared with that post-intended main flow shut-off or termination, drip release prevention (whether relative to a fuel pump nozzle or fuel container) effected by any prior art drip prevention valves.
One of the broad objects of at least one embodiment of the invention is to enhance the effectiveness of prevention of unwanted spillage of a fluid such as fuel from a fluid delivery conduit after an intended shut-off of a main valve element or other intended substantial termination of flow, as compared with any prior art drip prevention valves.
One of the broad objects of at least one embodiment of the invention is to reduce waste associated with unwanted spillage of a fluid such as fuel from a fluid delivery conduit after an intended flow termination. A related object of at least one embodiment of the present invention may be to enable cost savings for the seller and/or purchaser of fuel.
One of the broad objects of at least one embodiment of the invention is to effect a more volumetrically accurate filling procedure by substantially preventing flow of fluid such as fuel from a fluid delivery conduit after an intended flow termination, in an improved manner relative to any prior art drip prevention valves.
One of the broad objects of at least one embodiment of the invention is to reduce the emanation of vapors from the fluid into the ambient environment by substantially preventing flow of fluid such as fuel from a fluid delivery conduit after an intended flow termination. A related object of at least one embodiment of the invention is to improve the environment, particularly the air quality, and thus improve the health of persons inhaling that air.
One of the broad objects of at least one embodiment of the invention is to generally effect a more economical filling operation by substantially preventing flow of fluid such as fuel from a fluid delivery conduit after an intended flow termination in an improved manner relative to any prior art drip prevention devices.
One of the broad objects of at least one embodiment of the invention is to enable adaptation of existing, installed flow delivery conduits (including fuel pump nozzles and conduits of fuel conduits, as but two examples) by retrofitting, e.g., so that flow occurring after an intended fluid delivery shut-off (e.g., drips or drops, and/or a small stream) can be more effectively prevented without requiring a more costly purchase of, e.g., an entire fuel pump nozzle or fuel container, as compared with any prior art drip prevention devices. A related object of at least one embodiment of the present invention is to enable improved cost savings for the owner of the nozzle, savings which may be passed on to the purchaser of fluid, e.g., delivered via this nozzle.
One of the broad objects of at least one embodiment of the invention is to enable adaptation of flow delivery conduits in the factory so that the output product incorporates a fuel drip prevention valve element.
Naturally, further aspects and objects of the invention are disclosed throughout other areas of the specification and claims.